Oh hey @99999 , I’m starting to suspect that the asset is malformed:
We have some of the compressed data in our mesh primitives that we’re pointing to is pointing to some odd indices, such as the first primitive (which crashes our exporter, I assume we’re able to safely work around this oddity when loading)
I’m somewhat surprised that the glTF validator isn’t validating mesh primitives pointing to invalid draco compressed data indices, inspecting these indices manually via the glTF Tools for visual studio shows that indices 0 and 1 point to valid data, while index 6 for our second primitive does not.
Looking at the working asset (dzl-thumb.glb) the indices look more reasonable:
I assume something regressed in their attribute workflow between v1.0.5 and 1.1.45. Can you try to re-export the asset without compression, and compressing it manually using GitHub - CesiumGS/gltf-pipeline: Content pipeline tools for optimizing glTF assets.?
Also, @bghgary do you know of any other tools for inspecting draco compressed data?